Mohr envelope can be considered to be straight if the angle of internal friction φ is assumed to be__________$

• A. 90¬¨¬®‚Äö√†√ª
• B. >90¬¨¬®‚Äö√†√ª
• C. <90¬¨¬®‚Äö√†√ª
• D. None of the mentioned